Gear transmission



Feb. 3, 1931.

K. R. MANVILLE GEAR TRANSMISSION Filed May 9, 1929 3 Sheets-Sheet 1 Mm: 111911113. Mazzw'lle,

Patented Feb. 3, 1931 UNITED STATES PA ENT OFFICE KEITH R. MANVILLE, 01E HIGHLAND PARK, NEW JERSEY, ASSIGNOR TO INTER- NATIONAL MOTOR COMPANY, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE em mnsm ssron lpplicafion filed May 9,

The present invention relates to change speed mechanisms and controllin devices therefor, and embodies, more speci cally, an im roved transmission, wherein the length an weight of the shafts thereof are reduced and the transmission mechanism rendered more compact.

In the usual form of change speed mechanism having forward and reverse speeds, the

reverse countershaft must, of necessity, be sufficiently lon to enable the reverse gear to clear the sli ing gears which effect the low speed driving connections when the mechanism is operatin under forward speeds. It

is well known that the sliding gear for effecting a low speed drivin connection meshes both with the countersh'a ft gear corresponding to such driving connection and one of the sliding gears for effecting a reverse driving connection. In order that the sliding low speed gear will not simultaneously mesh with the countershaft gear and the reverse gear .(which also meshes with the countershaft gear) the reverse gears must normally be offset with respect to the, first mentioned gears. It will thus be seen that the lengths of the shafts and gear box must be increased by an amount equal to the width of the reverse gear which is required to be offset, that is,

displaced longitudinallyof the forward gears. This results in longer and weaker shafts with considerably more weight.

The present invention embodies a mecha-' nism in which the necessity for the additional length and weight of the shafts is eliminated by moving the reverse gears with the forward gears in the lowrange, thus keeping the reverse gears out of engagement with the for- 40 ward gears during such shifting.

An object of the invention is to provide a transmission which is more compact than the usual type of transmission.

A further object of the invention is to provide a transmission, the shafts of which are 1929. Serial No. 361,592.

shorter and of lighter weight than in existing designs.

A further object of the invention is to provide a transmission, the shafts of which are stronger by reason of the shortness thereof with greater ability to transmit torque.

A further object of the invention is to afford a means for taking off power from the transmission in opposite directions of rotation.

Further objects, not specifically enumerated above, will be apparent as the invention is described in connection with the accompanying drawings, wherein:

Figure 1 is a view in section, taken on line 1+1 of Figure 2, and looking in the direction of the arrows.

Figure 2 is a view in section, taken on line 2-2 of Figure 1, and looking in the direction of the arrows.

Figure 3 is a segmental View similar to Figure 2,-showing the selector lever shifted to a low speed selecting position.

Figure 4 is a view in section, taken on line 4-4 of Figure 3, and looking in the' direction of the arrows.

Figure 5 is a diagrammatic view of the improved transmission showing the space saved over existing designs by the construction embodied in the present invention.

Referring to the above drawings, a designates a transmission housing within which a driving shaft 2) is journaled. Driven shaft 0 delivers power to a desired mechanism and countershaft d is provided with the usual fixed gears (1, (P, and d for affording low, second and'third speeds, respectively. Reverse countershaft e is provided with a fixed gear e which engages with fixed gear d on countershaft d so that the reverse countershaft e, as weil as the countershaft d rotates continuously. I

A constant mesh gear d on countershaft d meshes with constant mesh driving gear 6 for driving th forward and reverse countershafts d and e, respectively, and sliding gears 0', c and c afiord a selective means for securing low, second, third and direct speeds. Sliding gear a is provided with in ternal teeth 0 for engaging the external teeth on gear 6, thus afl'ording a clutch for direct drive. Sliding gear e on the reverse counter shaft e is adapted to engage gear 0' on driven shaft 0 in the reverse driving positions in the usual manner.

A controlling housing f carries shifter rods 9, k, and i, shifter rod 9 carrying the reverse shifter fork g; shifter rod k carrying the third and fourth speed shifter fork h; and shifter rod 2' carrying the first and second speed shifter fork i. Shifter fingers 9 k and i are formed on the respective shifter rods 9, h and i to be engaged by a shifter lever as described hereinafter. The usual notch and detent mechanism is provided to lock the shifter rods in a desired V are moved with the guide plate to engage means for locking those shifter fingers not engaged by the shifter lever in a predetermined shift. Tt will be seen that lugs j sfich fingers in accordance with the selected s ift.

The control housing f carries a shifting lever which is mounted in a universal joint is and is adapted to be moved downwardly to efiect a reverse driving connection. Spring 70 normally opposes such axial movement of the shifting lever and prevents accidental shifting into reverse. A. flange f is mounted in the control housing to engage a shoulder 70 and thus normally prevent the engagement of the reverse shifting finger. Axial movement of the shifting lever downwardly, however, clears the flange ,f' and permits the reverse shifting finger to be engaged.

The lower extremit of the shifting lever is provided with for ed extensions k and 70 Forked extension k engages only shifting finger g to move the reverse sliding gear 6 VVhen extension 70 engages finger 9 ex tension k engages finger 2?, thus causing the reverse shifter fork to be moved simultaneously with the first and second speed shifter fork. Tn this manner, gear a is carried along with gear 0 and engagement thereof is prevented in the forward speeds. This connection is shown in Figure 3.

For securing third and fourth driving speeds, the shifting lever k is moved to the meme? position shown in Figure 2, at which time, extension 70 engages shifting finger k for moving gear 0 in either direction. In this condition, the reverse shifter fork g is not moved and, together with shifter fork i, is locked against movement by the lugs The reverse driving connection is secured by moving the lever downwardly in the position shown in Fi ure 2 and shifting to the right as viewed in igures 2 and 3. In this mamier, shoulder 71: clears flange f, and extension 70 engages shifting finger g to enable the reverse drive to be effected. Guide plate j moving with the extensions 70* and it cause the remaining shifter forks h and z" to be locked against movement since the right hand lug j engages the shifter fingers carried by each.

A power take-off d is provided from the countershaft d, while a second power take-ofi' e is provided from the reverse countershaft e. In this manner, a power take-ofi' rotating in either direction is provided and the transmission rendered quite useful in connection with special bodies where auxiliary driving mechanism is used.

Figure 5 illustrates the space saved over old and existing forms of transmissions by the construction described herein and it will be seen that modifications in the design and arrangement of parts may be made to suit individual installations. The transmission shown and described herein has been found to be highly successful and embodies a distinct improvement over existing designs.

I claim as my invention:

1. A. change speed mechanism including shiftable forward and reverse gears, a shifting means, forked extensions on the shifting means, a guide plate within which the extensions slide, means for mounting the guide plate to partake of movement transverse to the axes of thegears, shifter forks for shifting the gears, means on the forks for engagement selectively by the extensions, and means on the guide plate for preventing movement of the shifter forks not so enga ed.

2. A change speed mechanism including shiftable forward and reverse gears, a shifting means, forked extensions on the shifting means, a guide plate within which the extensions slide, shifter forks for shifting the gears, means on the forks for engagement selectively by the extensions, and means on the guide plate for preventing movement of the shifter forks not so en aged.

3. A change speed mec anism including shiftable forward and reverse gears, a shifting means,forkcd extensions on the shifting means, a guide plate within which the extensions slide, shifter forks for shifting the gears, and means on the forks for engagement selectively by the extensions.

al. A change speed mechanism including shiftable forward and reverse gears, said reverse gear being adapted to be engaged with one bf the shiftable forward gears to effect a reverse driving connection, a shifting means, independent shifter forks engaged selectively by the shifting means for shifting the gears, and means on the shifting means for engaging the reverse fork simultaneously with the engagement of the forward fork 

